Patents by Inventor Henricus J. M. Pigmans

Henricus J. M. Pigmans has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Magnetic recording element
    Patent number: 4732813
    Abstract: A magnetic recording element having a carrier and a magnetic coating provided thereon containing a magnetic pigment, a binder and a dispersing agent which is an amine or amide compound containing a sulfuric or sulfonic acid group.
    Type: Grant
    Filed: April 24, 1987
    Date of Patent: March 22, 1988
    Assignee: PD Magnetics, B.V.
    Inventors: Hendrikus F. Huisman, Henricus J. M. Pigmans
  • Composition and method for making magnetic recording elements
    Patent number: 4678705
    Abstract: A composition for making magnetic recording elements comprising finely divided particles of magnetic pigment dispersed in an organic medium comprising polymeric binder, lubricant, dispersing agent and porosity control agent dispersed in volatile organic solvent.
    Type: Grant
    Filed: July 3, 1985
    Date of Patent: July 7, 1987
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Hendrikus F. Huisman, Henricus J. M. Pigmans